Bolt's relay 38.10 WL

If you don’t mind my asking, how did you time it, and what video were you timing it from? I thought his stride looked a bit short (with good frequency), and he didn’t really put much distance into the person close to him (or at least it appeared that way to me).

Does anyone know how stride length on a straight is related to stride length on a curve? I suppose we could compare his anchor relay leg of this past weekend to his 2nd leg of the 2007 WC relay.